JP2005246182A - Ion exchange regeneration method for washing drainage and washing method by regenerated washing water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a method for controlling a content of electrolytic ions contained in a drainage generated by washing, and the like, and improving the water quality of the drainage to use washing water regenerated. <P>SOLUTION: The method comprises subjecting the cleaned drainage obtained by cleaning treatment of the washing drainage to an ion exchange to generate soft water when the electric conductivity of the cleaned drainage is ≤6,000 (μS/cm) and using the soft water as the regenerated washing water which can be reused as the washing water. The cleaned drainage made into the soft water can increase the surface active effect of a detergent and therefore has high detergency. A high degree of the detergency can thus be imparted thereto. The washing drainage discharged from a factory, and the like, can be improved in the water quality and can be recycled as the washing water and therefore a water rate can be reduced and the amount of the detergent can be saved by about 45% than usual. This method is effective for environmental conservation due to the reuse. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to cleaning water used at the time of cleaning in factories, large facilities, and the like, and more specifically, cleaning that regenerates cleaning wastewater discharged by cleaning and generates regenerated cleaning water that can be reused as cleaning water. It relates to a method for recycling wastewater.

  Japan is a country where a large amount of clear water can be obtained, and it consumes a large amount of river water, lake water, groundwater, rainwater, etc. as domestic water. In factories and the like, high-quality industrial water can be used at low cost, and a large amount of industrial water has been used for washing, air conditioning, food processing, brewing, and the like. In particular, although a large amount of water is required in the washing process, since the water is abundant, it has hardly been omitted to recycle waste water after washing. Therefore, in order to increase the cleaning efficiency, the type of detergent and the efficient usage method have been regarded as more important than the examination of the water quality of the cleaning water.

  In general, soap and synthetic detergent are mainly used as detergents. Soap is a fatty acid salt produced from fats and oils. Among them, sodium salts and potassium salts are mainly used as soaps. Synthetic detergents, on the other hand, were developed in Germany in 1834 and many improvements were made over the course of more than 100 years, leading to the emergence of high-quality synthetic detergents. In the 1960s, synthetic detergents were used in large quantities in Japan in the form of being used together with soap. Synthetic detergents have higher cleaning efficiency than soap and are particularly excellent in the ability to decompose fats and oils, so they are now used not only for industrial purposes but also in daily life.

  Synthetic detergents are produced in large quantities from petroleum and are widely used for industrial and household purposes. However, as environmental problems become apparent, the harmfulness of synthetic detergents has been pointed out. In particular, the use of synthetic detergents containing phosphorus has been regarded as a problem because it promotes eutrophication of rivers and lakes and leads to the destruction of the natural environment. In addition, it has been confirmed that a part of the synthetic detergent acts as an environmental hormone, and there is a concern that it adversely affects the biological world including humans. In recent years, as environmental pollution has been discussed at international conferences, awareness of protection of the natural environment has spread worldwide, and the use of synthetic detergents has become a problem in many countries, and the use of synthetic detergents is also being suppressed in Japan.

  As a result, at present, soaps that have been used conventionally are reviewed as detergents that replace synthetic detergents. It has been pointed out that soap is not harmful to the ecosystem because it is produced by alkaline treatment of fats and oils (hydrolysis with sodium hydroxide or potassium hydroxide), does not contain phosphorus and has no environmental hormone action. Therefore, it is preferable from the viewpoint of protecting the natural environment that soap is used instead of synthetic detergent. However, since the cleaning power is low as compared with the cleaning power of the synthetic detergent, the cleaning power is insufficient for cleaning excessively contaminated contaminants. For example, the dirt of commercial mops and mats after use is very severe, and it is conceivable that the cleaning efficiency is reduced in large-scale cleaning in a cleaning process mainly using soap.

In addition, the quality of industrial water used for cleaning and the like deteriorates year by year due to environmental pollution, and is a factor that further reduces the cleaning efficiency. Therefore, the conventional idea of improving the washing efficiency with detergents has been changed, and water quality improvement technology has been actively researched to improve the washing water used for washing and improve the washing power. . Normally, chlorine treatment, ozone treatment, ultraviolet treatment, activated carbon treatment, and the like are performed as tap water purification technologies, but these treatment costs are high and are limited to the water supply. Industrial water is difficult to apply as it is from the viewpoint of processing costs. For example, Japanese Patent Laid-Open No. 2001-170660 is published as a tap water reforming technique, and Japanese Patent Laid-Open No. 7-96283 is published as a cleaning water reforming technique.
JP 2001-170660 A JP-A-7-96283

FIG. 13 is a process diagram in the tap water reforming technique disclosed in Japanese Patent Laid-Open No. 2001-170660. Tap water, groundwater, etc. G1 is subjected to ion exchange treatment G2, and hardness components (metal ions) such as Ca ²⁺ and Mg ²⁺ are removed. Next, a cluster which is a molecular group of water is refined by tourmaline treatment G3 to generate cleaning active water G4. This publicly known technique shows that the cleaning efficiency is improved when the object to be cleaned is cleaned using the finally obtained cleaning active water, compared to cleaning with simple tap water or groundwater. However, since this known technique performs a two-stage process called a tourmaline process in addition to the ion exchange process, there is a weak point that the processing cost is high. In addition, tap water and groundwater used are highly clear water, and no mention is made as to whether or not the same washing efficiency can be obtained when this two-stage treatment is applied to the waste water after washing. Moreover, since reuse of waste water after washing is not considered, there is a weak point that causes environmental pollution when discharged into the environment.

FIG. 14 is a process diagram in the washing water reforming technique disclosed in Japanese Patent Laid-Open No. 7-96283. Tap water / ground water F1 is subjected to an ion exchange treatment F2 to remove metal ions such as Ca ²⁺ and Mg ²⁺ to soften the water, and a tourmaline treatment F3 generates cleaning active water F4. This active water F4 for washing has a characteristic that can be washed F5 without using a detergent, and the oil released from the object to be washed by the washing can be separated into oil and water F6 by adding tap water. The separated oil / water is separated and recovered by oil recovery and moisture discharge F7. This known technique also performs a two-stage treatment of ion exchange and tourmaline on clear tap water or groundwater, so that the processing cost becomes high. Further, there is no description or suggestion as to whether or not the same cleaning effect can be obtained with respect to the waste water after cleaning. Moreover, since reuse of waste water after washing is not considered, there is a weak point that causes environmental pollution when discharged into the environment.

  As described above, both of the known techniques are intended to improve the water quality by increasing the detergency by performing ion exchange and tourmaline treatment on clear water such as tap water and groundwater. However, such a conventional method always requires expensive clarified water, resulting in high water costs. In addition, an expensive material called tourmaline is used, which makes the processing facility expensive. In addition, since the washing wastewater is spontaneously released without being reused, it becomes a technology that does not contribute at all to effective use of water resources and environmental protection, which are currently lacking worldwide. Therefore, in order to realize environmental conservation and reduction of cleaning costs, a technology that can recycle and reuse cleaning wastewater is required.

Dirty textiles such as clothes and mops and mats, and detergents and chemicals used when washing contain a significant amount of Na compounds (Na ⁺ ) and hardness components (eg Ca ²⁺ , Mg ²⁺ ) If these textiles are washed, a large amount of Na ⁺ , Ca ²⁺ and Mg ²⁺ will be contained in the waste water after washing (wash waste water). In general, it has been considered that water containing Na ⁺ cannot ion-exchange hardness components such as Ca ²⁺ and Mg ²⁺ . That is, a phenomenon occurs in which hardness components such as Ca ²⁺ and Mg ²⁺ are discharged without being ion-exchanged, and this phenomenon is said to be a hardness leakage phenomenon. Hereinafter, the hardness leakage phenomenon will be described in detail with reference to FIG.

FIG. 15 is an explanatory diagram of the hardness leakage phenomenon. (15A) is an explanatory diagram of a state in which Na ⁺ is attached to the ion exchange resin. Consider the case where waste water containing Ca ²⁺ , Mg ²⁺ and Na ⁺ flows into the ion exchange resin tank from above. (15B) is an explanatory diagram of a state where these ion groups pass through the ion exchange resin, and shows a state where Ca ²⁺ is exchanged with Na ⁺ attached to the ion exchange resin. At this stage, Ca ²⁺ contained in the waste water is adsorbed by the ion exchange resin, and Na ⁺ adhering to the ion exchange resin is released and ion exchange is performed. (15C) is a diagram of a hardness leakage phenomenon. The state where Ca ²⁺ once absorbed in the ion exchange resin is exchanged with Na ⁺ contained in the waste water and is released from the ion exchange resin into the waste water is shown. That is, it is shown that Ca ²⁺ once absorbed is released again into the waste water. Therefore, when Na ⁺ is contained in the waste water, ion exchange is impossible, and this phenomenon is called hardness leakage phenomenon.

  In the conventional technical common sense, it has been believed that it is impossible to remove hardness components from waste water having high salinity by ion exchange. That is, since high salinity remains in the washing wastewater of textile products, it has become common sense in the field of washing technology that it is impossible to ion-exchange the washing wastewater due to the action of this high salinity.

The inventors of the present invention have focused on the concentration of electrolyte such as Na compound contained in the waste water, and found that the leakage phenomenon of hardness does not occur when the concentration of the electrolyte is below a certain value, thereby completing the present invention. Is. The idea was that if the content of the electrolyte contained in the wastewater could be measured, Ca ²⁺ and Mg ²⁺ , which are hardness components in the waste water, could be removed, and the salt-containing waste water could be softened. Since the electrolyte is mainly composed of a Na compound, the electrolyte ions are mainly Na ⁺ . The present invention has been completed by paying attention to the fact that the concentration of the electrolyte ions can be obtained by measuring the electrical conductivity (σ) of the waste water discharged after washing. Therefore, the object of the present invention is to determine whether or not the drainage can be ion-exchanged by measuring the electrical conductivity (σ) of this drainage, and if possible, perform ion exchange and recycle the drainage. And providing a method for reusing as washing water.

  In the first aspect of the present invention, purification wastewater discharged by washing is subjected to purification treatment to produce purified wastewater, and the purification wastewater has an electrical conductivity of 6000 (μS / cm) or less. This is an ion-exchange regeneration method for washing wastewater, in which the wastewater is ion-exchanged to generate soft water, and this soft water is regenerated washing water that is reused as washing water.

  In the second embodiment of the present invention, the cleaning wastewater discharged by cleaning is subjected to purification treatment to generate purified wastewater, and the electrical conductivity of the purified wastewater is set within a range of 6000 (μS / cm) or less. This is an ion exchange regeneration method for cleaning wastewater that is ion-exchanged for the purified wastewater to produce soft water when the electrical conductivity is lower than the standard allowable electrical conductivity, and this soft water is reused as cleaning water.

  In the third embodiment of the present invention, when the electrical conductivity of the purified wastewater exceeds the standard allowable electrical conductivity, water is added to the purified wastewater, and the dilution treatment is performed until the purified wastewater becomes equal to or lower than the standard allowable electrical conductivity. This is an ion exchange regeneration method for washing wastewater.

  The fourth aspect of the present invention is an ion exchange regeneration method for cleaning wastewater, in which the electrical conductivity of purified wastewater is constantly measured by a measurement sensor, and the addition of water is continued until the measured value falls below the reference allowable electrical conductivity. is there.

  In the fifth aspect of the present invention, the electrical conductivity of the purified wastewater is measured by a measurement sensor, and the amount of water added so that the electrical conductivity of the purified wastewater is equal to or lower than the reference allowable electrical conductivity is calculated from this measured value. This is an ion exchange regeneration method for washing wastewater, in which a calculated addition amount of water is injected into the purified wastewater.

  A sixth embodiment of the present invention is a cleaning method for cleaning an object to be cleaned with a detergent using the regenerated cleaning water according to any one of the first to fifth embodiments.

  In the seventh aspect of the present invention, the regenerated cleaning water and the fresh water described in any one of the first to fifth embodiments are mixed to form cleaning water, and the object to be cleaned is washed with a detergent using this cleaning water. It is a cleaning method.

  The eighth aspect of the present invention is a cleaning method for cleaning an object to be cleaned using the cleaning method according to the sixth or seventh aspect, and rinsing the object to be cleaned with fresh water at least in the final stage.

According to the first aspect of the present invention, the electrical conductivity σ (μS / cm) of the purified wastewater generated by subjecting the washed wastewater discharged by the cleaning to purification treatment is 6000 (μS / cm) or less. In this case, ion exchange becomes possible and water softening treatment becomes possible. In the following, the electrical conductivity of 6000 (μS / cm) will be referred to as the limit allowable electrical conductivity. The electrical conductivity of the purified wastewater has a correlation with the concentration of metal ions contained in the purified wastewater, and the electrical conductivity increases as the content of an electrolyte such as a Na compound in the purified wastewater increases. Conventionally, when Na ⁺ is contained in the purified waste water, it has been considered that the above-described hardness leakage phenomenon occurs and the ion exchange of the hardness component cannot be performed. The present inventors pay attention to the correlation between the content (concentration) of electrolyte ions (mainly Na ⁺ ) contained in the purified waste water and the hardness leak, and the electrical conductivity of the purified waste water is less than the limit allowable electrical conductivity. If present, the present invention has been completed by demonstrating that ion exchange can be performed. As a result, it was possible to remove Ca ²⁺ , Mg ^{2+ and the} like contained in the purified waste water by ion exchange, and to soften the purified waste water. Since the purified waste water that has been softened can activate the surface active action of the detergent, it has a high detergency. This soft water having high detergency can be used as reclaimed wash water and can be reused as wash water. The lower limit value of the electrical conductivity of the purified waste water is zero. The smaller the electrical conductivity of the purified waste water, the lower the salinity and the more efficient ion exchange. However, even clarified water has a finite electrical conductivity, so it is impossible to obtain water with zero electrical conductivity except in special cases (ultra pure water). Therefore, the lower limit value of the electrical conductivity of the purified waste water may be an electrical conductivity of water quality that can be actually used that is equal to or lower than the limit allowable electrical conductivity. The purified water that has been softened is referred to as regenerated cleaning water, and has high detergency even without being subjected to tourmaline treatment, so that the object to be cleaned can be efficiently cleaned.

According to the second aspect of the present invention, when the electrical conductivity σ of the purified waste water is equal to or lower than the reference allowable electrical conductivity σ ₀ (μS / cm) set within a range equal to or lower than the limit allowable electrical conductivity, Ion exchange can be performed as described above, and the purified waste water can be softened. The electric conductivity that can be realized by the present invention may be equal to or less than the limit allowable electric conductivity, but the electric conductivity varies depending on the degree of contamination of the waste water, the cleaning method, and the waste water treatment method. Therefore, the reference allowable electric conductivity (σ ₀ (μS / cm)) is set as an upper limit value of the electric conductivity that is actually possible within a range equal to or lower than the limit allowable electric conductivity. The value is arbitrarily set to 4000, 3000, 2000 (μS / cm) or the like according to the quality of the purified waste water. By appropriately adjusting the numerical value of the reference allowable electrical conductivity (σ ₀ ), the purified waste water can be freely softened, and the quality of the purified waste water can be improved according to the degree of contamination of the object to be cleaned. If the numerical value of the standard permissible electrical conductivity (σ ₀ ) is set low, a higher degree of softening of the purified waste water can be achieved and it can be used for various washing applications. This purified water that has been softened is referred to as regenerated washing water, and has high detergency even without being subjected to tourmaline treatment, so that the object to be washed can be efficiently washed.

According to a third aspect of the present invention, when the electrical conductivity of the cleaning wastewater exceeds the reference allowable electric conductivity (sigma _0), the reference acceptable electrical conductivity (sigma ₀₎ by fresh water or the like until the following Dilution treatment can be performed. If the electrical conductivity of the purified wastewater is equal to or lower than the reference allowable electrical conductivity (σ ₀ ), as described above, the purified wastewater can be ion-exchanged and can be regenerated as washing water. Since tap water, ground water, river water, etc. can be used for the dilution treatment, it can be easily diluted, and the dilution amount can be freely adjusted in accordance with the cleaning application within the range of the standard allowable electrical conductivity (σ ₀ ) or less. Therefore, the purified waste water whose electrical conductivity is diluted below the standard permissible electrical conductivity (σ ₀ ) can be ion-exchanged and regenerated to wash water having high detergency, and can be reused as regenerated wash water.

According to the fourth aspect of the present invention, if the reference allowable electric conductivity (σ ₀ ) is set to an arbitrary value, the measurement sensor constantly measures the electric conductivity of the purified waste water as the reference allowable electric conductivity ( Since it can be diluted with fresh water or the like until σ ₀ ) or less, it is suitable when a large amount of objects to be cleaned are continuously processed. In particular, when a large amount of objects to be cleaned having the same degree of dirt is cleaned, since the cleaning water having a high cleaning power can be continuously regenerated, the running cost in the cleaning process can be greatly reduced.

According to the fifth aspect of the present invention, the electric conductivity of the purified waste water is measured by the measuring sensor, and the amount of dilution of fresh water or the like is calculated so as to be equal to or lower than the standard allowable electric conductivity (σ ₀ ). It can be applied to non-uniform dirt. In addition, since the amount of dilution of new water or the like can be accurately calculated, it is possible to reduce the cost associated with the cleaning process, and to reduce the cost for treating the discharged waste water.

According to the 6th form of this invention, the regenerated washing water in any one of the 1st-5th form can be used. That is, the first is regenerated washing water that regenerates purified waste water having an electric conductivity of 6000 (μS / cm) or less. The second is regenerated wash water that regenerates purified wastewater having a reference electrical conductivity (σ ₀ ) or less set within an electric conductivity of 6000 (μS / cm) or less. Third, when exceeding the electric conductivity reference acceptable electrical conductivity a (sigma _0), which is the reference tolerance electric conductivity (sigma ₀₎ reproducing the washing water obtained by reproducing the purification wastewater subjected to dilution treatment below. The fourth is regenerated washing water in which the purified waste water is regenerated by constantly measuring the electric conductivity to be equal to or lower than the reference allowable electric conductivity (σ ₀ ). The fifth is regenerated wash water in which purified water is regenerated by calculating the amount of water injected so that the electrical conductivity is equal to or lower than the reference allowable electrical conductivity (σ ₀ ). These five types of regenerated cleaning water are softened by ion exchange and have high detergency as regenerated cleaning water. Therefore, if the object to be cleaned is washed with a detergent using any one of these five types of regenerated washing water, even higher detergency is exhibited. For example, taking rental cleaning supplies as an example, compared to washing with fresh water without ion exchange, 45% for household mats, 40% for household mops, 25% for commercial mops, an average of 40 overall % Detergent usage can be reduced. Therefore, when only regenerated washing water is used as washing water, waste water after washing is less likely to be drained into sewage and rivers, etc., so the purchase amount of tap water and industrial water and sewage treatment costs can be reduced, and washing costs are reduced. Can be reduced. In addition, since the amount of detergent used can be reduced, it can contribute not only to cleaning costs but also to protection of the natural environment.

According to the seventh aspect of the present invention, cleaning can be performed by mixing fresh water or the like with any of the five types of regenerated cleaning water. As described above, the five types of recycled cleaning water have high cleaning power. New water includes tap water, industrial water, groundwater, and river water. These new waters contain electrolytes such as Na compounds. Usually, the hardness of Japanese tap water or industrial water is generally 50 to 300 (ppm). Compared to this, the regenerated wash water contains much less Ca ²⁺ , Mg ^2+, etc. by ion exchange treatment. As a result, higher cleaning power can be realized as compared with cleaning using only fresh water. Therefore, if cleaning is performed by mixing fresh water, etc., with any of these five types of regenerated cleaning water, the amount of detergent used can be reduced compared to cleaning using only fresh water, etc., and the cost of cleaning is reduced. And natural environment protection at the same time.

  According to the 8th form of this invention, after wash | cleaning with the washing | cleaning method as described in a 6th form or a 7th form, a to-be-cleaned object can be rinsed with fresh water. By rinsing with fresh water, not only the detergent absorbed in the object to be cleaned is washed away, but also electrolytes such as Na compounds adhering to the object to be cleaned can be removed. New water includes tap water, industrial water, groundwater, river water, etc. and can be used easily. The amount of fresh water used and the number of times of rinsing can be adjusted as appropriate depending on the degree of contamination of the object to be cleaned and the type of dirt, and the cleaning effect required for the object to be cleaned can be achieved.

  Hereinafter, embodiments of a method for regenerating cleaning wastewater and a method for cleaning with regenerated cleaning water according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a process diagram for constantly measuring the electrical conductivity (σ) of waste water after washing to generate regenerated washing water. The cleaning wastewater discharged by the cleaning A1 is subjected to a normal wastewater treatment by the purification treatment A2 and becomes purified wastewater. Thereafter, electrical conductivity measurement A3 is always performed by the measurement sensor, and determination A4 of σ ≦ σ ₀ (μS / cm) (σ ₀ ≦ 6000) is performed. If the electrical conductivity of the purified wastewater is less than or equal to the standard allowable electrical conductivity (σ ₀ ), the purified wastewater is softened by ion exchange A6 and the purified wastewater is regenerated as wash water, and this regenerated wash water is regenerated and washed water tank Store in A7. When the electrical conductivity σ of the purified waste water is not the standard allowable electrical conductivity σ ₀ or less, the dilution process A5 is performed to reduce the electrical conductivity σ of the purified waste water to the standard allowable electrical conductivity σ ₀ or less, and the ion exchange A6 The purified waste water is regenerated and stored in the regenerated washing water tank A7. That is, while the processes A3, A4, A5 are continuously repeated, the purified waste water diluted until the electric conductivity σ becomes σ ₀ or less and diluted to σ ₀ or less receives the ion exchange A6. Since this regeneration method constantly measures the electrical conductivity of the purified waste water, it is optimal for washing a large amount of objects to be cleaned continuously.

FIG. 2 is a process diagram for measuring the electrical conductivity of the waste water after washing, calculating the dilution amount, and generating regenerated washing water. The cleaning wastewater discharged by the cleaning B1 is subjected to normal purification treatment (drainage treatment B2) to become purified wastewater. Thereafter, electrical conductivity measurement B3 is performed by the measurement sensor, and determination B4 of σ ≦ σ ₀ (μS / cm) (σ ₀ ≦ 6000) is performed. When the electrical conductivity σ of the cleaning wastewater is equal to or less than the reference allowable electrical conductivity σ ₀ , the purified wastewater is softened by ion exchange B7 and regenerated as cleaning water, and this regenerated cleaning water is regenerated and washed water tank B8. Store in. When the electrical conductivity σ of the purified waste water is not equal to or less than the reference allowable electrical conductivity σ ₀ , a dilution amount calculation B5 is performed, and a dilution process B6 is performed so that σ ≦ σ ₀ . By this dilution treatment, the electrical conductivity σ of the purified waste water is adjusted to be equal to or lower than the reference allowable electrical conductivity σ _0, and the purified waste water is regenerated by ion exchange B7 and stored in the regenerative washing water tank B8. The dilution amount is calculated as follows. If the amount of purified waste water to be diluted is V ₀ , the electrical conductivity is σ, the diluted addition amount is V, and the reference allowable electrical conductivity is σ ₀ , the amount of electrolytic ions (mainly Na ⁺ ) in the purified waste water is constant. Since the electric conductivity is proportional to the amount of electrolytic ions, the following equation is established. V ₀ σ = (V + V ₀ ) σ _{0 When} this equation is solved for V, V + V ₀ = V ₀ σ / σ ₀ is obtained, and V = V ₀ (σ / σ ₀ −1) is obtained. In this way, the diluted addition amount V is calculated. This regeneration method has the advantage that various cleaning objects can be individually washed as a batch process because the purified wastewater can be diluted by measuring the electrical conductivity of the purified wastewater and calculating the dilution amount.

FIG. 3 is a process diagram of the actual regeneration cleaning water generation in the present embodiment. The washed waste water after the washing is subjected to a solid precipitation process in the settling tank C1, and is coagulated and precipitated with a coagulant such as a sulfuric acid band in the coagulation process tank C2. Next, a decolorization process is performed by the decolorization cation flocculant process C3. These processes C1, C2, and C3 correspond to the purification process A2 or B2 described above, and as a result, purified waste water is generated. Furthermore, measurement C4 of the electrical conductivity of the purified waste water is performed, and determination C5 of σ ≦ σ ₀ (μS / cm) (σ ₀ ≦ 6000) is made. When the electrical conductivity σ of the purified waste water is less than the standard allowable electrical conductivity σ ₀ , the purified waste water is softened by the ion exchange C7 and regenerated as the cleaning water. Store in C8. When the electrical conductivity σ of the purified waste water is not equal to or less than the reference allowable electrical conductivity σ ₀ , the dilution process C6 is performed, and the electrical conductivity σ of the purified waste water is adjusted to be equal to or lower than the standard allowable electrical conductivity σ ₀ . Thereafter, the purified waste water is regenerated by ion exchange C7 and stored in the regenerated washing tank C8. The two kinds of processing methods are applied to the dilution process C6.

FIG. 4 is an apparatus diagram for generating regenerated cleaning water in the present embodiment. The waste water discharged from the cleaning tank 2 is purified in the purification treatment tank 4 through the piping, and is stored in the purification drain tank 6 from the purification drain injection pipe 5. The electrical conductivity σ of the stored purified waste water 8 is measured by the measurement sensor 10, and the determination of σ ≦ σ ₀ (μS / cm) (σ ₀ ≦ 6000) is performed by the control device 12. When the electrical conductivity σ of the purified waste water 6 is equal to or lower than the reference allowable electrical conductivity σ ₀ , the valve 20 is opened, and the purified waste water 8 moves to the ion exchange tank 22 and is softened. As a result, the purified waste water 8 is regenerated as cleaning water, and the regenerated cleaning water 28 is stored in the regenerated cleaning water tank 26. When the electrical conductivity σ of the purified waste water 8 is not equal to or lower than the reference allowable electrical conductivity σ ₀ , the valve 16 of the new water introduction pipe 14 is opened, and fresh water injection 18 is made into the purified waste water tank 6.

  FIG. 5 is a process diagram showing a cleaning method when only regenerated cleaning water is used in the present embodiment. The regenerated cleaning water stored in the regenerated cleaning water storage tank D1 is sent to the cleaning tank D2, and the object to be cleaned D3 and the detergent charging D4 are performed in the cleaning tank D2, and after the cleaning D5 and the rinse D6, Waste water is sent to waste water treatment D7. The number of times of rinsing is appropriately adjusted according to the degree of soiling of the object to be cleaned, and the rinsing order may be repeated not only after rinsing but also rinsing and rinsing again. In the final stage, it will be rinsed with fresh water. By rinsing with fresh water at the final stage, salt remaining in the object to be cleaned is removed.

  FIG. 6 is an apparatus diagram showing a cleaning method when only regenerated cleaning water is used in the present embodiment. The regenerated cleaning water 28 stored in the regenerated cleaning water tank 26 is injected into the cleaning tank 2 through the regenerated cleaning water injection pipe 30. The detergent 32 and the object to be cleaned 34 are supplied and cleaning is performed. The cleaning tank 2 contains a cleaning product 34.

  FIG. 7 is a process diagram showing a cleaning method when using mixed cleaning water of regenerated cleaning water and fresh water in the present embodiment. The regenerated wash water stored in the regenerated wash water storage tank E1 is sent to the wash tank E2, and fresh water is charged E3 in the wash tank E2, and the regenerated wash water and fresh water are mixed. After the object to be cleaned E4 and the detergent input E5 are performed and the cleaning E6 is performed, the waste water after the cleaning through the rinse E7 is subjected to a drainage treatment E8. Also in this case, the number of times of rinsing is appropriately adjusted according to the degree of contamination of the object to be cleaned, and the rinsing order may be repeated after washing and rinsing again. In the final stage, rinsing is performed with fresh water to remove salt remaining in the object to be cleaned.

  FIG. 8 is an apparatus diagram for realizing a cleaning method in the case where mixed cleaning water of regenerated cleaning water and fresh water is used in the present embodiment. The regenerated cleaning water 28 stored in the regenerated cleaning water tank 26 is injected into the cleaning tank 2 through the regenerated cleaning water injection pipe 30. Fresh water is injected into the cleaning tank 2 through a new water injection pipe 36, and a detergent 32 and an object to be cleaned 34 are introduced. The mixing ratio of regenerated washing water and fresh water is adjusted as appropriate. The cleaning tank 2 contains a cleaning product 34.

  In the present embodiment, 500 g of a uniform soiled mop piece and five artificially contaminated cloths were used as objects to be cleaned. The mop piece was obtained by cutting 10 mops into a size of 3 cm × 3 cm. This object to be cleaned was put into a small bucket washing machine for test, and washed with 6 L (liter) of 60 ° C. regenerated cleaning water, 22.5 g of detergent mainly composed of soap and 50 g of inorganic builder (alkali agent) for 12 minutes. . After washing, the object to be washed is rinsed with regenerated washing water (room temperature) for 2 minutes, and then again washed with 6 L of regenerated washing water at 60 ° C., 15 g of soap-based detergent and 500 ppm of chlorine-based disinfecting bleach. did. The object to be cleaned was rinsed twice with fresh water (room temperature) twice, and then the oil was soaked as an adsorbent, dehydrated and dried. The degree of cleaning of the washed mop piece was determined visually, the artificially contaminated cloth was determined based on the degree of contamination, and both determinations were comprehensively evaluated. With respect to the overall judgment result, “Excellent” is indicated by “◎”, “Good” is indicated by “◯”, “Yes” is indicated, “No” is indicated, “No” is indicated, and “No” is indicated when Absolutely impossible.

[Examples 1 to 7: Purified waste water having a total hardness of 25 ppm]
FIG. 9 is a list of Examples 1 to 7 (Table 1). The total amount of metal ions excluding Na ⁺ is the total hardness, and the electrical conductivity (μS / cm) of purified wastewater with a total hardness of 25 (ppm) is adjusted to seven types of 1000, 3000, 5000, 6000, 7000, 8000, and 10,000. did. These seven types of purified waste water were ion-exchanged to produce regenerated wash water. The total hardness of this regenerated cleaning water was measured, and the above cleaning was performed using this regenerated cleaning water. The total hardness of the regenerated wash water has dropped sharply from 25 ppm, demonstrating that the hardness component has been removed by ion exchange. The electrical conductivity was adjusted by adding bow glass (Na ₂ SO ₄ ). As a result, no problems occurred in Examples 1-7.

[Comparative Example 1]
For comparison, general tap water was used as washing water, and washing tests similar to those in Examples 1 to 7 were performed. This tap water is not subjected to ion exchange treatment. It was revealed that the amount of detergent used in Examples 1, 2 and 3 using the regenerated washing water of the present invention was about 50% of the amount of detergent used when the tap water was used. Accordingly, it has been found that the present invention can achieve a saving of about 50% of the amount of detergent and a saving in water usage fee.

[Examples 8 to 14: Purified waste water having a total hardness of 42 ppm]
FIG. 10 is a list of Examples 8 to 14 (Table 2). The electrical conductivity of the purified wastewater having a total hardness of 42 (ppm) was adjusted to 7 types in the same manner as in Examples 1 to 7, and each of the 7 types of purified wastewater was subjected to ion exchange to generate regenerated washing water. The total hardness of this regenerated washing water was measured, and this regenerated washing water was used for washing in the same manner as in Examples 1-7. As a result, defects occurred in Example 13 and Example 14. The reason is considered to be that the total hardness value of the regenerated cleaning water is large.

[Comparative Example 2]
For comparison, a cleaning test was performed using tap water as cleaning water. It was revealed that the amount of detergent used in Examples 8 and 9 using the regenerated washing water of the present invention is about 55% of the amount of detergent used when tap water is used. Accordingly, it has been found that the present invention can realize a saving of about 45% of the amount of detergent and a saving in water usage fee.

[Examples 15 to 21: Purified waste water having a total hardness of 98 ppm]
FIG. 11 is a list of Examples 15 to 21 (Table 3). The electrical conductivity of the purified wastewater with a total hardness of 98 (ppm) was adjusted to 7 types in the same manner as in Examples 1 to 7, and each of the 7 types of purified wastewater was subjected to ion exchange to generate regenerated washing water. The total hardness of this regenerated washing water was measured, and this regenerated washing water was used for washing in the same manner as in Examples 1-7. As a result, defects occurred in Example 19, Example 20, and Example 21. The reason is considered to be that the total hardness value of the regenerated cleaning water is large.

[Comparative Example 3]
For comparison, a cleaning test was performed using tap water as cleaning water. It was revealed that the amount of detergent used in Examples 15 and 16 using the regenerated washing water of the present invention was about 60% of the amount of detergent used when tap water was used. Accordingly, it has been found that the present invention can achieve a saving of about 40% of the amount of detergent and a saving in water usage fee.

[Examples 22 to 28: Purified waste water having a total hardness of 136 ppm]
FIG. 12 is a list of Examples 22 to 28 (Table 4). The electrical conductivity of the purified waste water having a total hardness of 136 (ppm) was adjusted to 7 types in the same manner as in Examples 1 to 7, and each of the 7 types of purified waste water was subjected to ion exchange to generate regenerated washing water. The total hardness of this regenerated washing water was measured, and this regenerated washing water was used for washing in the same manner as in Examples 1-7. As a result, defects occurred in Example 26, Example 27, and Example 28. The reason is considered to be that the total hardness value of the regenerated cleaning water is large.

[Comparative Example 4]
For comparison, a cleaning test was performed using tap water as cleaning water. It was revealed that the amount of detergent used in Examples 22 and 23 using the regenerated washing water of the present invention was about 65% of the amount of detergent used when tap water was used. Accordingly, it has been found that the present invention can realize a saving of about 35% of the amount of detergent and a saving in water usage fee.

  From the results of Examples 1 to 28, when the electrical conductivity of each effluent having a total hardness of 25, 42, 98, and 136 (ppm) is 6000 or less, the clarified effluent is regenerated according to the present invention and regenerated washing water. This regenerated wash water has been demonstrated to have a high detergency. In this example, washing was performed only with the regenerated washing water obtained by the present invention. As a result, it was found that the average amount of detergent used can be reduced by about 45% compared to normal tap water. Therefore, it is obvious that the same effect can be obtained by adding fresh water to the regenerated washing water to obtain washing water and washing with the mixed washing water.

  It has been clarified that the present invention can regenerate cleaning wastewater and regenerate it as regenerated cleaning water having high detergency. The use of this regenerated wash water can reduce the amount of detergent used by about 45%, and it can be regenerated and used any number of times to save water bills. At the same time, the amount of drainage into the environment is reduced, which is useful for environmental conservation. Accordingly, it can be used not only for cleaning textile products but also for non-textile products, and in particular, has an advantage that it can be used for cleaning dust control products such as mops and mats.

In this invention, it is a process figure for always measuring the electrical conductivity of purified waste water, and producing | generating regenerated washing | cleaning water. In this invention, it is a process figure for measuring the electrical conductivity of purified waste water and calculating the amount of dilution, and producing | generating regenerated washing water. It is a flowchart of regeneration washing water generation in an embodiment of the present invention. It is an apparatus figure of the regenerated washing water generation in the embodiment of the present invention. It is process drawing which showed the washing | cleaning method at the time of using only the reproduction | regeneration washing | cleaning water in this embodiment. It is an apparatus figure showing a washing method at the time of using only regenerated washing water in this embodiment. It is process drawing which showed the washing | cleaning method at the time of using the mixed washing water of the reproduction | regeneration washing | cleaning water and new water in this embodiment. It is the apparatus figure which showed the washing | cleaning method at the time of using the mixed washing water of the reproduction | regeneration washing water and new water in this embodiment. It is a list figure (Table 1) of Examples 1-7. It is a list figure (Table 2) of Examples 8-14. It is a list figure (Table 3) of Examples 15-21. It is a list figure (Table 4) of Examples 22-28. It is process drawing of the reforming technique of the tap water which the conventional Unexamined-Japanese-Patent No. 2001-170660 has shown. FIG. 5 is a process diagram of a cleaning water reforming technique disclosed in Japanese Unexamined Patent Publication No. 7-96283. It is explanatory drawing of a hardness leak phenomenon.

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Washing tank 4 Purification treatment tank 5 Purification drainage injection pipe 6 Purification drainage tank 8 Purification drainage 10 Measurement sensor 12 Control device 14 New water injection pipe 16 New water injection valve 18 New water injection 20 Drain valve 22 Ion exchange tank 26 Regenerative cleaning water tank 28 Recycled Wash Water 30 Recycled Wash Water Injection Pipe 32 Detergent 34 Washed Object 36 New Water Injection Pipe

Claims (8)

Purified wastewater discharged by washing is purified to generate purified wastewater. When the electrical conductivity of the purified wastewater is 6000 (μS / cm) or less, the purified wastewater is ion-exchanged to generate soft water. A method for ion-exchange regeneration of cleaning wastewater, characterized in that this soft water is regenerated cleaning water that is reused as cleaning water. When cleaning wastewater discharged by cleaning is subjected to purification treatment to generate purified wastewater, and the electrical conductivity of the purified wastewater is equal to or less than a standard allowable electrical conductivity set within a range of 6000 (μS / cm) or less In addition, an ion-exchange regeneration method for cleaning waste water, wherein the purified waste water is ion-exchanged to generate soft water, and the soft water is used as regenerated cleaning water that is reused as cleaning water. 3. The method according to claim 2, wherein when the electrical conductivity of the purified wastewater exceeds the reference allowable electrical conductivity, water is added to the purified wastewater, and dilution treatment is performed until the purified wastewater is equal to or lower than the reference allowable electrical conductivity. Ion exchange regeneration method for washing wastewater. 4. The method for ion exchange regeneration of cleaning wastewater according to claim 3, wherein the electrical conductivity of the purified wastewater is constantly measured by a measurement sensor, and the addition of water is continued until the measured value becomes equal to or less than the reference allowable electrical conductivity. The electrical conductivity of the purified wastewater is measured by a measurement sensor, and the amount of water added so that the electrical conductivity of the purified wastewater is equal to or less than the reference allowable electrical conductivity is calculated from the measured value. The method for ion exchange regeneration of washing wastewater according to claim 3, wherein water is added to the purified wastewater. 6. A cleaning method, wherein the object to be cleaned is cleaned with a detergent using the regenerated cleaning water according to claim 1. A cleaning method comprising mixing the regenerated cleaning water and fresh water according to any one of claims 1 to 5 to form cleaning water, and using this cleaning water to clean the object to be cleaned with a detergent. A cleaning method, comprising: cleaning an object to be cleaned using the cleaning method according to claim 6 or 7, and rinsing the object to be cleaned with fresh water at least in a final stage.

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